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3D Coordination
See also: Concurrent Engineering

The process in which information models are used to determine field conflicts via Clash Detection software or visual inspection. 3D coordination is accomplished by comparing proposed 3D geometry from discipline models aggregated into a federated model. 3D elements for all objects are required to perform 3D coordination, and thus a deviation from the TXDOT LOD standards may be required for specific model elements. α


As-built Record
See also: Asset Information Model (AIM)

Traditionally, “marked up” plan sets that denote any changes to the project that occurred during construction. Increasingly, there is interest in collecting digital asset information in construction to support maintenance and operation of the asset. α

Asset Information Model (AIM)
See Also: Project Information Modeling (PIM):

A model that contains data and information to support the management and operation of the asset. α

An asset information model is essentially a BIM model complemented with all the required information essential to operate and manage the asset after construction. An asset can refer to civil or infrastructure work or any other dedicated asset within the bigger BIM model. μ

Asset Management
See also: Asset Information Model (AIM):

A strategic and systematic process for managing assets and programming maintenance and replacement activities. Asset Management Systems are often GIS databases that track the current condition of the assets. The information is updated routinely, when assets are inspected, or when maintenance or construction actions occur. α


Non-graphical data that is part of a model element definition. α

Automated Machine Guidance (AMG)

The use of real-time positioning equipment with 3D digital data to guide or control the blade on construction equipment, resulting in real-time construction layout without the need for physical markers such as stakes or hubs. α


BCF Dataset (BCF File)

Dataset with data structured according to the BCF standard. Can be exchanged in a (zip)file, or as JSON through an API. β

Building Information Modeling (BIM)
See Also: Computer-Aided Design and Drafting (CAD/CADD)

The use of a digital model of a built asset to facilitate design, construction, and operation processes to form a reliable basis for decisions. BIM may also be used as a noun to describe the digital model. α

A building information model (BIM) is a digital depiction or representation of various components of a building or facility, usually in a 3D format. The three-dimensional model is linked to a central database consisting of information about materials, components, systems, products, and their attributes. μ

BCF Application Programming Interface (BCF API)

Standard API to exchange BCF data between online applications. β

BIM Collaboration Format (BCF)

Standard to exchange information about the contents inside an IFC Dataset. Can be exchanged in a file (xml) or through an API (JSON). β

BIM Coordination (Clash Detection)

BIM coordination allows various stakeholders to work with each other throughout the entire lifecycle of a BIM project. This is done to avoid chances of clashes and detect the same at early stages to minimize wastage of resources and for achieving cost-efficiency. Clash detection helps discover conflicts between various elements- structural, MEP through a digital approach via the BIM model. μ

BIM Coordination (Clash Rendition)

Clash rendition is the process undertaken to minimize chances of clashes and speed up the process of clash detection between Building Information Models (BIM) developed by different teams. Clash rendition is done to reduce errors and minimize costs. μ

BIM Execution Plan (BEP)
See also: Project Execution Plan (PxP)

A plan to manage the use of BIM, especially collaboration and information delivery, to accomplish the project goals. α

A BIM execution plan is drafted to manage project delivery. BEP is categorized into pre-contract and post-contract BEP where pre-contract BEP outlines the proposal in response to the information requirements and post-contract BEP consists of delivery details. μ

BIM Manager
See also: BIM Execution Plan (BEP)

The individual, normally identified in a BEP, responsible for overseeing the use of BIM on the project. α

BIM Objects

A BIM object contains detail information about a component and its geometry representing its physical characteristics within a project model. μ

Business Process Modelling Notation (BPMN)

OMG standard for specifying business processes in a business process model. β

buildingSMART Data Dictionary (bSDD)

data dictionary with classifications, properties, relations and translations. The data in the bSDD can be connected to IFC and to each other. The bSDD is a service of buildingSMART. β


Common Data Environment (CDE)

A service that collects, stores, manages, and shares information through a managed process. α

Common Data Environment (CDE) is a shareable information repository that can be used by all the stakeholders in a BIM project. All the data related to a BIM model is created, stored and shared via the CDE through cloud storage that can be accessed by various departments/stakeholders to improve coordination and boost productivity. μ

Computer-Aided Design and Drafting (CAD/CADD)
See also: Building Information Modeling (BIM)

A category of computer software that is used to develop designs for a variety of disciplines. CADD software typically uses an object-oriented approach to apply mathematical rules that automate the process of drafting roadway designs. 3D digital design data is a common output of the application of CADD software. α

Concurrent Engineering
See also: 3D Coordination

The process in which discipline model managers provide managed access to model authors for other disciplines to facilitate real-time interdisciplinary design coordination. α

Conformance Level

The level of IFC that a software implementation supports. β

See also: Parametric

A relationship between two or more elements in a model, which should be maintained in any modifications made to the base element. The rebar layout is constrained by the slab geometry. α

Construction Inspection

The process in which the owner’s representative monitors and documents construction quality assurance and measures and verifies pay item quantities for completed work. α

Construction Simulation

The process in which a 3D model is connected to a construction schedule to simulate the sequence of construction activities. 3D models need to be organized with elements (usually in 3D) segmented and grouped according to the work breakdown structure in the schedule. α

Contract Document
See also: Model as the Legal Document

Contract documents are a collection of clearly identifiable documents that describe the requirements and terms for a construction project. The contract documents typically include plans, specifications, and working drawings. The specification defines “plans and working drawings,” as well as how to coordinate contract documents in the case of a conflict. Models and/or CAD documents may be included in the definition of “Plans and Working Drawings” or defined as specific contractual entities in the Specifications or Special Provisions. α

Contractor Estimating
See also: Engineer’s Estimate:, Quantity Take-off

Part of the bid process in which the contractor takes off quantities from the contract documents to prepare a price for each bid item. α


Data Exchange
See also: Extract Transform Load: Information Exchange

The process of taking data structured under a source schema to transform and restructure into a target schema, so the target data are an accurate representation of the source data within specified requirements and minimal loss of content. α

Data exchange specification is a standard specification for electronic file formats for facilitating the exchange of digital data between various BIM software to promote interoperability. μ

Design Authoring
See also: Existing Conditions Modeling

The process in which 3D design software is used to develop information models based on specific roadway and structural criteria to convey design intent for construction. The core functions of design authoring include development and analysis of the design elements. Many design objects are developed per TXDOT Model Development Standards to achieve the desired LOD for determining pay item quantities. However, not all the CAD files containing these design objects are contractual deliverables. Please refer to the TXDOT Contractual File Deliverables for specific requirements. α

Design Review

The process in which an information model is used to review and provide feedback related to multiple design aspects. These aspects include evaluation of design alternatives and environmental constraints, review and validation of geometric design criteria, and completeness or quality of overall design. α

Digital Delivery
See also: Model as the Legal Document

An exchange of asset and project information that occurs using digital data as opposed to analog representations comprised of paper or from which the information must be extracted manually. Digital delivery makes data available to be used across TXDOT by all disciplines. α

Digital Twin

Twin Initially conceived of for smart manufacturing, a digital twin is a digital representation of a physical asset that contains a 3D digital model of the physical asset, as well as information about the asset such as its properties, functions, evaluative properties, and other analytical context. α

Discipline Model
See also: Federated Model

A model or linked models related to a single discipline. The superstructure model, substructure model, and detailing models are linked together into a federated Structural Discipline Model. α


Electronic Document Management System (EDMS)
See also: Common Data Environment (CDE)

A system for storing, retrieving, sharing and otherwise managing electronic documents. α

Engineer’s Estimate
See also: Contractor Estimating:, Quantity Take-off

The estimated construction cost as determined by the Designer. Designers use QTO to determine pay item quantities and multiply those quantities by reasonable rates (usually from historical bids) to produce an aggregate cost. α

Engineer of Record (EOR)
See also: Model Element Author

The professional engineer who signs and seals the project documents and assumes professional responsibility for the design. The EOR may supervise the work of subordinate Model Element Authors who create the model under the EOR’s direction. α

Exchange Information Requirements (EIR)

Requirement A nn-technical description of the information needed by a business process to be executed, as well as the information produced by that business process. α

A machine-readable file (within buildingSMART usually in JSON) that defines the information requirements for a project. This is often the combination between IFC plus additional classifications and property sets. Definitions from the bSDD can be included as well. β

Existing Conditions Modeling
See also: Design Authoring

The process to create a 3D model of existing conditions for a roadway and/or bridge project, including an existing ground surface and the demarcation of features such as above and underground and utilities, structures, fences, and trees. It may also include the modeling of existing pavement structures. α

Extract Transform Load (ETL)
See also: Data Exchange:, Information Exchange

Extract, Transform, and Load are three discrete database processes that can be combined in one action to copy data from one database into another database that presents the information differently (i.e. transformed). α


Federated Model
See also: Discipline Model

A model that is compiled by integrating different discipline models together into one model through either linking and/or importing. α

A federated model is an integrated model developed by collating different individual models into a single model. This is done by importing several models into a single model via the process of collaborative working. μ

For Information Only (FIO)

See also: Contract Document:, Model as the Legal Document:, Reference Information:

Supplemental information provided to the contractor that is not contractually-binding and used at the contractor’s risk. The soils report was provided with the bid package For Information Only. α


Geodatabase (GDB)
See also: Geoprocessing Tool:, Spatial Data

A database that is designed to store, query, and manipulate spatial data. A geodatabase may hold multiple datasets of different types. α

Geoprocessing Tool
See also: Geodatabase (GDB):, Spatial Data

A software tool that manipulates spatial data to produce a transformed spatial dataset. A geoprocessing tool was applied to the roadway data for Utah to create a dataset defined by a 50-foot buffer around all the north/south US routes in Utah. α

Graphical Data
See also: Non-graphical Data:, Spatial Data

Data conveyed using shape and arrangement and/or location in space. α


Industry Foundation Classes (IFC)
See also: Open Data

A non-proprietary data schema and format to describe, exchange and share the physical and functional information for the assets within a facility. IFC the ISO standard for BIM and is being extended to roadway and bridge asset classes. α

Standard (agreement) for the semantic definition of objects and structuring of information within the built environment. IFC consists of descriptions of objects, relations, properties and the definition of several file formats to exchange the data. β

IFC specification is a data standard managed by buildingSMART international that governs the data format for describing, sharing and exchanging information used in the building and facility management sector. Fundamentally, it includes definition, schemas, and libraries of IFC- a neutral data format. μ

IFC Dataset
See also: Industry Foundation Classes (IFC)

Dataset with data structured according to the IFC standard. Usually exchanged in a file, but could also be exchanged through an API. β

IFC Specification
See also: Industry Foundation Classes (IFC):, Schema

Definition of extensions and specializations on top of the schema. buildingSMART defined Property Sets are also on this level. These can be domain specific. β

IFC specification is a data standard managed by buildingSMART international that governs the data format for describing, sharing and exchanging information used in the building and facility management sector. Fundamentally, it includes definition, schemas, and libraries of IFC- a neutral data format. μ

Industry Foundation Classes Query Language (ifcQL)

Standard query language to filter IFC Datasets. Basis for future buildingSMART APIs β

Information Delivery Manual (IDM)

ISO Standard to define workflows (BPMN), exchange requirements and machine readable ‘Functional Parts’. β

An information delivery manual is developed to identify different construction processes and articulate information required at every stage. IDM is developed using a standard format outlined in ISO 29381-1. The information delivery manual is designed to make the required information available to stakeholders whenever required. μ

Information Delivery Specification (IDS)

Information Delivery Specification. An XML Based buildingSMART standard to define (project) requirements. Supports objects, properties, attributes, materials and more. β

Information Exchange

See also: Data Exchange

Packages of information passed from one party to another in a BIM process, or the act of passing such information. Can be a deliverable. Parties involved agree upon and understand what information content and format will be exchanged. Agreed information exchanges are typically documented in the BEP using the MPS. α

Information Requirements

See also: Information Exchange

A specification for what, when, how and for whom information is to be produced. α

Information Framework for Dictionaries (IFD)

ISO standard (12006 part 3) defining a framework for object-oriented information. It was an inspiration to build the first bSDD. β


Level of Detail
See also: Level of Development (LOD)

Often confused with LOD, level of detail describes only the amount of geometric detail in a model element, not the amount of engineering intent. Highly-detailed model elements may be placed in a model as place-holders with no engineering intent. Though detail often increases in parallel with development, observing the detail of a model element is not an effective way to determine its development or the appropriate uses. α

Level of detail is a standard defined in PAS 1192-2 which depicts the Level of Model Detail and Level of Information Detail. While the level of model detail outlines the graphical content on models at each stage, the level of model information is associated with non-graphical content within models at different stages. Level of detail can be schematic, conceptual or defined. μ

Level of Development (LOD)
See also: Level of Information (LOI):, Level of Visualization (LOV):, Model Progression Specifications (MPS)

A qualitative designation that communicates the degree of engineering intent behind a 3D model element (or group of model elements) and defines the authorized uses for which the model element is sufficiently developed. Normally the LOD will increase through the design development process as defined in the MPS. α

Level of Development (LOD) specification allows AEC professionals to articulate Building Information Models at different stages of the design and construction process. It is a form of a standard reference that promotes clarity, accuracy, and reliability of the content of a BIM model. μ

Level of Information (LOI)
See also: Level of Development (LOD)

A description of the quality of the non-graphical information attached to the model elements. α

Level of Visualization (LOV)
See also: Level of Development (LOD)

A qualitative designation that communicates the degree of visual enhancement given to the 3D model elements, to suit the needs of different target audiences. Generally, non-technical audiences need color-realistic geometry or even photo-realistic materials to be able to understand bridge models. α


Hyperlinks that can be applied to geometry to allow a user to connect to and access a wide range of external files and formats. These links can be used to link to web addresses, networked folder locations, files and/or folders located in a CDE, or bookmarks within the file. α


See also: Model Progression Specifications (MPS)

Data used for the description and management of documents and other containers of information. Metadata is usually structured data embedded within the file. However, it could include an external document that describes pertinent information to others on the assumptions and basis for the 3D models, such as the geospatial metadata (grid/ground coordinate system definitions), intended uses of the 3D models, approximations and simplifications (e.g., removing minor curvature from analysis models). A MPS is important metadata that accompanies a Federated Model. α


A representation of a system that allows for investigation of the properties of the system. (EN ISO 29481-1:2016). The roadway and bridge models were delivered in CADD files. α

Model as the Legal Document (MALD)
See also: Digital Delivery

A form of digital delivery in which a model comprises the primary construction contract document, preeminent in importance as defined by the Specification or Special Provision. α

Model-based Design and Construction (MBDC)
See also: Digital Delivery

An approach to design and construction in which a model forms the primary means of communicating the construction requirements. α

Model Element
See also: Level of Development (LOD):, Model Element Author (MEA):, Model Progression Specifications (MPS)

An entity within a model that represents a physical object or an abstract concept (e.g., alignment, north arrow). α

Model Element Author (MEA)
See also: BIM Execution Plan (BEP):, Engineer of Record (EOR):, Model Element

The individual, normally identified in a BEP and/or MPS, responsible for creating a specific model element or group of model elements. The MEA may work under the direct supervision of an EOR who assumes professional responsibility for the design represented in the model. α

Model Breakdown Structure (MBS)
See also: Model Progression Specifications (MPS)

A classified list of model elements. An MBS is the basis for a Model Progression Specification. α

Model Manager
See also: BIM Execution Plan (BEP):, BIM Manager:, Model Element

The individual, normally identified in a BEP, responsible for a specific discipline model. α

Model Development Standards (MDS)

Model Progression Specifications (MPS)
See also: Model Breakdown Structure (MBS)

A specification that defines how the LOD for individual model elements increases over the project milestones. The MPS will assign a specific, minimum LOD to each model element for each milestone. The LOD typically increases from milestone to milestone. α

Model View Definition (MVD)
See also: Industry Foundation Classes (IFC)

A subset of the overall IFC schema to describe data exchange for a specific use or workflow, narrowing the scope depending on the need of the receiver. A Transportation Pooled Fund Project is working on defining an IFC MVD for the design-to-construction exchange of bridge information. α

An MVD has three purposes: (1) defining a subset of IFC required to fulfil a purpose (comparable with EIR); (2) adding additional restriction to that subset; (3) defining an expected level of implementation in software (comparable with Conformance Levels). β


Native Format
See also: Open Specification:, Proprietary Specification

A generic term to describe the proprietary file formats associated with the model authoring software. α

Non-graphical Data
See also: Attribute:, Graphical Data:, Property

Data that describes attributes and properties of a model element that do not relate to its physical dimensions or location. α


Open Data
See also: Open Specification

Data that is publicly available and free to use or reuse without restrictions. TXDOT makes a variety of open data available to the public via the TXDOT Data Portal. α

Open Common Data Environment Application Programming Interface (openCDE API)

Standard API to exchange information between online connected data environments. β

Open Specification

See also: Industry Foundation Classes (IFC):, Proprietary Specification

A specification for data that is structured according to an open schema that is freely available and not controlled by any one particular vendor. Open specifications are intended to facilitate data exchange. α


See also: Constraint

An approach to creating a model whether the physical dimensions are constrained by mathematical rules such that the model can be manipulated by changing individual property definitions. α

Pay Item Quantities
See also: Contractor Estimating:, Engineer’s Estimate:, Quantity Take-off

A schedule of work items for which the contractor will be paid and an estimated number for each item. α

Planning and Programming

The process in which Asset Management Systems and GIS are used to evaluate properties and conditions of existing assets in a particular area to determine scope of work, high level cost estimation, and prioritization of projects to be added to the construction program. α

Project Execution Plan (PxP)
See also: BIM Execution Plan (BEP)

A plan to manage the use of BIM, especially collaboration and information delivery, to accomplish the project goals. α

Project Information Modeling (PIM)
See also: Asset Information Model (AIM)

A model that contains information to support the design and construction of the asset. α

See also: Attribute

Non-graphical information that describes a model element. The Modulus of Elasticity is a property of a girder. α

Dynamic, often per project defined, set of properties for a specific object(type). β

Proprietary Specification
See also: Open Specification

A specification for data that is structured according to a proprietary schema. Proprietary data can usually only be read and written by one vendor’s software products. α

See also: Industry Foundation Classes (IFC)

International agreed Property Set definition for a specific object(type) or purpose. Part of IFC. β


Quantity Take-off (QTO)
See also: Contractor Estimating:, Engineer’s Estimate

The process of estimating the pay item quantities. The designer performs QTO to determine the Engineer’s Estimate. QTO is also part of the Contractor Estimating process to bid the job. α

Quantity take-offs refer to an accurate measurement of materials and labor required for completing a construction project. An estimator develops quantity-takeoffs during the pre-construction process which are used for outlining the scope of construction. μ


Reference Information
See also: Contract Document:, For Information Only (FIO)

Supplemental information provided to the contractor that is not contractually-binding and used at the contractor’s risk. The soils report was Reference Information provided with the bid package. α


See also: Industry Foundation Classes (IFC)

A formalized model for structuring information. α

Definition of the core elements, resources and relations in IFC. This is the part of IFC that is common for every extension and domain. β

Spatial Data
See also: Geodatabase:, Graphical Data:

Data that is associated with a spatial reference system, such as State Plane coordinates. Spatial data may be raster (e.g. aerial photography) or vector (e.g. point, line, or polygon). α


Use Case Management Tool (UCM Tool)

Service from buildingSMART to share and find exchange (information) requirements (EIR) and workflows (BPMN). Use-cases are organized with meta information to search and filter. β